Reputation: 2496
I have a control on my GUI which I would like to make visible only case when I run BackgroundWorkers (many different operations). Some of these operations last less than 500ms, and I feel that making the control visible for so short a time is useless. Therefore, I would like to make the control visible only if a BackgroundWorker has already been working for 500ms.
Upvotes: 1
Views: 662
Reputation: 2982
You can use a Timer inside the BackgroundWorker and call the ReportProgress method once 500ms have passed.
In the UI thread you then just need to handle the ProgressChanged event and show/hide your control as required.
public partial class Form1 : Form
{
/// <summary>
/// Timer.
/// </summary>
private Timer timer = new Timer();
/// <summary>
/// Initializes a new instance of the <see cref="Form1"/> class.
/// </summary>
public Form1()
{
InitializeComponent();
backgroundWorker1.WorkerReportsProgress = true;
backgroundWorker1.DoWork += BackgroundWorker1DoWork;
backgroundWorker1.ProgressChanged += BackgroundWorker1ProgressChanged;
timer.Interval = 500;
timer.Tick += TimerTick;
}
/// <summary>
/// Handles the Tick event of the timer control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
void TimerTick(object sender, EventArgs e)
{
timer.Enabled = false;
backgroundWorker1.ReportProgress(99);
}
/// <summary>
/// Handles the Click event of the button1 control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.EventArgs"/> instance containing the event data.</param>
private void Button1Click(object sender, EventArgs e)
{
timer.Enabled = true;
backgroundWorker1.RunWorkerAsync();
}
/// <summary>
/// Handles the DoWork event of the backgroundWorker1 control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.ComponentModel.DoWorkEventArgs"/> instance containing the event data.</param>
private void BackgroundWorker1DoWork(object sender, DoWorkEventArgs e)
{
BackgroundWorker worker = sender as BackgroundWorker;
// Do your work...
Thread.Sleep(2000);
}
/// <summary>
/// Handles the ProgressChanged event of the backgroundWorker1 control.
/// </summary>
/// <param name="sender">The source of the event.</param>
/// <param name="e">The <see cref="System.ComponentModel.ProgressChangedEventArgs"/> instance containing the event data.</param>
private void BackgroundWorker1ProgressChanged(object sender, ProgressChangedEventArgs e)
{
label1.Visible = (e.ProgressPercentage == 99);
}
}
Upvotes: 0
Reputation: 24723
Leverage the ReportProgress method on the BackgroundWorker
. You can place whatever you want in the state parameter and then perform the calculation accordingly.
public class MyObject
{
public DateTime TimeStarted {get; set;}
}
Then in your ProgressChanged
event handler...
private void backgroundWorker1_ProgressChanged(object sender, ProgressChangedEventArgs e)
{
if(DateTime.Now.Subtract(((MyObject)e.UserState).TimeStarted).TotalMilliseconds > 500)
{
//show your control
}
}
Upvotes: 0
Reputation: 942548
Just start a timer at the same time you start the BGW:
private void button1_Click(object sender, EventArgs e) {
timer1.Enabled = true;
backgroundWorker1.RunWorkerAsync();
}
private void timer1_Tick(object sender, EventArgs e) {
timer1.Enabled = false;
myControl1.Visible = true;
}
private void backgroundWorker1_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) {
timer1.Enabled = myControl1.Visible = false;
}
Upvotes: 1